CN1395301A - Method for manufacturing mixed integrated circuit device - Google Patents

Abstract

A method for manufacturing a hybrid integrated circuit device, in which the position of the hybrid integrated circuit substrate in the horizontal direction is fixed in the mold cavity during the molding process. In the present invention, the position of the hybrid integrated circuit substrate 31 can be fixed by making the part where the specific wires 39a, 39b connected to the first connecting portion 53 keep a certain distance contact the guide pins 46a, 46b provided on the mold. Since the interval of the specific wires 39a, 39b is independent of the number of terminals of the hybrid integrated circuit substrate 31, the model can be shared even if the number of terminals is different.

Description

Method for manufacturing hybrid integrated circuit device

technical field

The present invention relates to a manufacturing method of a hybrid integrated circuit device, and relates to a manufacturing method of a hybrid integrated circuit device in which a resin package is formed on a hybrid integrated circuit substrate by transfer molding.

Background technique

Generally, there are mainly two packaging methods for hybrid integrated circuit devices.

The first method is to package with a device in the shape of a lid placed on a hybrid integrated circuit substrate on which circuit elements such as semiconductor devices are mounted, that is, a device generally called a box member. The structure sometimes adopts a hollow structure or a structure in which resin is additionally injected.

The second method is to use injection molding as a molding method for semiconductor ICs. For example, it is shown in JP-A-11-330317. The injection molding method generally uses a thermoplastic resin, for example, a resin heated to 300° C. is injected with a high injection pressure and once filled in the mold to encapsulate the resin. Compared with the transfer mold, since the polymerization time of the resin after filling the mold is unnecessary, there is an advantage that the working time can be shortened.

A conventional hybrid integrated circuit device using an injection mold and its manufacturing method will be described below with reference to FIGS. 9 to 12. FIG.

First, as shown in FIG. 9, an aluminum (hereinafter referred to as Al) substrate 1 is used as a metal substrate for description.

The surface of the Al substrate 1 is anodized, and a resin 2 having good insulating properties is formed on the entire upper surface. However, this oxide may be omitted in consideration of withstand voltage.

The resin package 10 is formed of a support member 10a and a thermoplastic resin. That is, the substrate 1 placed on the support member 10a is covered with a thermoplastic resin by injection molding. Then, the contact portion between the support member 10a and the thermoplastic resin is melted by the injected high-heat thermoplastic resin, thereby realizing a fully molded structure.

Here, as the thermoplastic resin, what is called PPS (polyphenylene sulfide) is used.

The injection temperature of the thermoplastic resin is very high, about 300° C., and there is a problem that the high-temperature resin melts the solder 12 to cause solder failure. Therefore, a thermosetting resin (such as epoxy resin) is potted in advance to cover the joint of solder, the thin metal wire 7 , the active element 5 and the passive element 6 to form the overcoat layer 9 . In this way, it is possible to prevent the resin from being injected into the thermoplastic resin, especially the thin wires (approximately 30 to 80 μm) from falling down or breaking.

The resin package 10 is formed in two stages. In the first stage, a supporting member 10a is placed on the back of the liner 1 to secure the thickness of the back of the liner 1 when a gap is provided between the back of the substrate 1 and the mold and resin is filled therebetween with high injection pressure. In the second stage, the substrate 1 mounted on the supporting member 10 a is covered with a thermoplastic resin by injection molding. Then, the contact portion between the support member 10a and the thermoplastic resin is melted by the injected high-heat thermoplastic resin, thereby realizing a fully molded structure. Here, the thermoplastic resin used as the supporting member 10a is preferably a resin having the same thermal expansion coefficient as that of the substrate 1 .

Next, a method of manufacturing a conventional hybrid integrated circuit device using an injection mold will be described with reference to FIGS. 10 to 12 .

Figure 10 is a flow chart of the process, including the process of preparing the metal substrate, the insulating layer forming process, the copper foil pressing process, the partial nickel plating process, the copper foil etching process, the chip loading process, the wire bonding process, the potting process, and the wire connection process, support member mounting process, injection molding process, lead wire cutting process and other processes.

11 and 12 show cross-sectional views of each step. In addition, the drawings are omitted for processes that are clear without illustration.

First, FIG. 11(A) and FIG. 11(B) show a step of preparing a metal substrate, an insulating layer forming step, a copper foil press-fitting step, a partial nickel plating step, and a copper foil etching step.

In the step of preparing the metal substrate, the role as the substrate is prepared in terms of heat dissipation, substrate strength, substrate shielding properties, and the like. Furthermore, in this embodiment, an Al substrate 1 having a thickness of about 1.5 mm, for example, is used which has good heat dissipation.

Next, on the aluminum substrate 1, a resin 2 having good insulating properties is also formed on the entire surface. Copper conductive foil 3 constituting a hybrid integrated circuit is press-fitted on insulating resin 2 . Nickel plating 4 is applied to the entire surface of the copper foil 3 in accordance with its adhesiveness to, for example, the thin metal wires 7 that electrically connect the copper foil 3 serving as a lead-out electrode and the active element 5 .

Then, nickel plating 4a and conductive path 3a are formed by known screen printing or the like.

Next, FIG. 11(C) shows a chip mounting process and a wire bonding process.

The active element 5 and the passive element 6 are mounted on the conductive path 3a formed in the previous process with a conductive paste such as solder 12 to realize a predetermined circuit.

12(A) and 12(B) show a potting step, a wire connection step, and a supporting member installation step.

As shown in FIG. 12(A), in the potting process, before the subsequent injection molding process, the joints of the solder, metal thin wires 7, and active components are potted with a thermosetting resin (such as epoxy resin) in advance. 5 and passive components 6 to form an overcoat layer 9 .

Next, external wires 8 for outputting and inputting signals from the hybrid integrated circuit are prepared. Then, external leads 8 are connected via external connection terminals 11 and solder 12 formed on the outer peripheral portion of substrate 1 .

Then, as shown in FIG. 12(B), the support member 10a is placed on the hybrid integrated circuit substrate 1 to which the external leads 8 and the like are connected, and the substrate 1 is placed on the support member 10a, so that the following steps can be ensured. The thickness of the resin encapsulation body 10 on the back side of the substrate 1 when the injection mold is mounted.

Fig. 12(C) shows an injection molding process and a wire cutting process.

As shown in the figure, after the substrate 1 is potted with thermosetting resin and the overcoat layer 9 is formed, the resin package 10 is formed by injection molding. At this time, the contact portion between the support member 10a and the thermoplastic resin is melted by the injected high-heat thermoplastic resin, and the resin package 10 having a full-molded structure is formed.

Finally, the external lead 8 is cut according to the purpose of use, and the length of the external lead 8 is adjusted.

Through the above steps, the hybrid integrated circuit device shown in FIG. 9 is completed.

In addition, transfer mode methods are often implemented in semiconductor chips. In the hybrid integrated circuit device formed by transfer molding, for example, a semiconductor element is fixedly mounted on a lead frame made of copper. Also, the semiconductor element and the wiring are electrically connected through a gold (hereinafter referred to as Au) wire. This is because thin Al wires are easily bent, and ultrasonic waves are required for bonding, so the bonding time is long, so they cannot be used. Therefore, at present, there is no hybrid integrated circuit device that will be directly transfer-die-mounted by a metal substrate composed of a single metal plate on which circuits are formed and wire-bonded by Al thin wires.

Contents of the invention

In the injection molded hybrid integrated circuit device, it is necessary to prevent the thin metal wires 7 from being bent or broken due to the injection pressure during molding, and to prevent the solder 12 from flowing due to the temperature during injection. Therefore, in the conventional structure shown in FIG. 9, the overcoat layer 9 formed by potting is adopted to cope with the above-mentioned problems.

However, injection molding is performed after potting with a thermosetting resin (such as epoxy resin) to form the overcoat layer 9, so there is a problem that the material cost and operating cost of the thermosetting resin are consumed.

In the existing hybrid integrated circuit device using a lead frame and formed by a transfer mold, the semiconductor elements are fixedly mounted on the isolation island, so the heat generated by the semiconductor elements is dissipated from the fixed installation area, but the heat dissipation area is limited, and there is a problem of heat dissipation. problem of poor sex.

As described above, in wire bonding of resin packages, Au wires that are highly resistant to resin injection pressure are used, so transfer molding using Al wires has not been practiced yet. In addition, since Al thin wires are bonded by ultrasonic waves, the contracted parts are weak, and the modulus of elasticity is low, so that they cannot withstand the injection pressure of the resin, so they tend to bend quickly.

In the case of encapsulating the hybrid integrated circuit substrate with a transfer mold, it is necessary to fix the position of the hybrid integrated circuit substrate in the horizontal and thickness directions within the mold, but when the fixing pins are brought into contact with the rear surface of the hybrid integrated integrated circuit substrate During positioning, there is a problem that the rear surface of the substrate is exposed after packaging, resulting in degradation of withstand voltage.

An object of the present invention is to provide a device for fixing a hybrid integrated circuit substrate at a predetermined position within a mold during a transfer molding process.

In order to solve the above problems, the manufacturing method of the semiconductor integrated circuit device of the present invention includes the following steps: preparing a hybrid integrated circuit substrate whose surface has been subjected to insulation treatment at least; forming a conductive pattern on the substrate; fixing a semiconductor element or a passive element; electrically connecting wires on said substrate; molding a thermosetting resin on at least a surface of said substrate by means of a transfer mold.

In the present invention, the molding process is characterized in that the specific lead wires of the lead frame of the hybrid integrated circuit substrate are bonded with solder at a constant interval, and the specific lead wires are connected to the connection part provided at the lead wire interruption and the device is connected. Make contact with the guide pins on the model. Thereby, the positioning of the lead frame and further the positioning of the hybrid integrated circuit substrate can be performed, so that the conventional problems can be solved. Moreover, by positioning the hybrid integrated circuit substrate, the back surface of the hybrid integrated circuit substrate can be covered with a certain thickness of resin with good heat dissipation, and the heat dissipation of the hybrid integrated circuit device can be improved.

Description of drawings

Fig. 1 is (A) plane view of the hybrid integrated circuit device of the present invention, (B) sectional view;

Fig. 2 is (A) sectional view, (B) plane view of hybrid integrated circuit device of the present invention;

Fig. 3 is a flow chart of the manufacturing method of the hybrid integrated circuit device of the present invention;

4 is a diagram illustrating a method of manufacturing a hybrid integrated circuit device of the present invention;

5 is a diagram illustrating a method of manufacturing a hybrid integrated circuit device of the present invention;

6 is a diagram illustrating a method of manufacturing a hybrid integrated circuit device of the present invention;

7 is a diagram illustrating a method of manufacturing a hybrid integrated circuit device of the present invention;

8 is a diagram illustrating a method of manufacturing a hybrid integrated circuit device of the present invention;

Fig. 9 is a cross-sectional view of a conventional hybrid integrated circuit device;

10 is a flowchart of a manufacturing method of a conventional hybrid integrated circuit device;

11 is a diagram illustrating a method of manufacturing a conventional hybrid integrated circuit device;

12 is a diagram illustrating a method of manufacturing a conventional hybrid integrated circuit device;

Detailed ways

Next, a hybrid integrated circuit device according to Embodiment 1 of the present invention will be described with reference to FIG. 1 and FIG. 2 .

First, the structure of this hybrid integrated circuit device will be described with reference to FIG. 2 . As shown in FIG. 2(A), the hybrid integrated circuit device 31 employs a substrate with good heat dissipation in consideration of heat generated by semiconductor elements etc. fixedly mounted on the substrate 31 . In this embodiment, the case where the aluminum substrate 31 is used will be described. In addition, although an aluminum (hereinafter referred to as Al) substrate is used for the substrate 31 in this embodiment, it does not need to be particularly limited. For example, this embodiment can also be realized by using a printed circuit board, a ceramic substrate, a metal substrate, etc. as the substrate 31 . Moreover, a copper substrate, an iron substrate, an iron-nickel substrate, or an AlN (aluminum nitride) substrate can be used as the metal substrate.

The surface of the Al substrate 31 is anodized, and an insulating resin 32 such as epoxy resin having good insulating properties is formed on the entire surface. However, if the withstand voltage is not considered, the metal oxide may not be provided.

On the resin 32, a conductive path 33a made of copper foil 33 (see FIG. 5) is formed, and the Al substrate 31 is overcoated with, for example, an epoxy resin to protect the conductive path 33a except for the electrical connection portion. Active elements 35 such as power transistors, small-signal transistors, or ICs, and passive elements 36 such as chip resistors and chip capacitors are mounted on the conductive circuit 33a via solder 40 to realize a predetermined circuit. Here, instead of using solder locally, it is also possible to use silver paste or the like for electrical connection. When the active elements 8 such as semiconductor elements are mounted face-up, they are connected by thin metal wires 37 . For the fine metal wire 37 , in the case of a power semiconductor element, for example, an Al wire of about 150 to 500 μmφ is used. It is usually called thick line. In the case of a half-power system or a small-signal system semiconductor element, for example, an Al wire of approximately 30 to 80 μmφ is used. It is usually called thin line. An external lead 39 made of a conductive member such as copper or iron nickel is connected to the external connection terminal 38 provided on the outer peripheral portion of the Al substrate 31 via solder 40 .

The present invention is characterized in that a resin package is directly formed on the active element 35, the passive element 36, the thin Al wire 37, and the like on the hybrid integrated circuit substrate 31.

That is, in the resin package 41 , the thermosetting resin used for the transfer mold has a low viscosity and a curing temperature lower than the melting point of, for example, 183° C., the solder 40 or the like used for the above-mentioned connection means. Thus, as shown in FIG. 9 , the overcoat layer 9 formed by potting with a thermosetting resin (for example, epoxy resin) in a conventional hybrid integrated circuit device can be removed.

As a result, especially thin metal wires with a diameter of about 40 μm, which electrically connect small-signal ICs and the like to the conductive circuit 33a, will not lie down even if they are directly filled with the thermosetting resin at the time of transfer molding. , broken or bent. Especially for thin Al wires, it is important to prevent bending.

Next, as shown in FIG. 2(B), the external lead 39 is led out of the resin package 41, and the length of the external lead 39 is adjusted according to the purpose of use. Holes 42 are formed at two places on the resin package 41 as indentations on the side opposite to the side from which the external leads 39 are led out. The holes 42 are produced by pressing the pins 47 (see FIG. 6 ) to fix the substrate 31 during the transfer molding described above, and remain after the resin package 41 is formed.

As shown in FIG. 1(A) , the hole 42 is formed in the outer peripheral portion 43 of the substrate 31 , that is, a portion of the substrate 31 where no circuit or the like is formed. In addition, since the holes 42 are formed in the insulating resin 32 in the outer peripheral portion 43 of the substrate 31, there is no problem in terms of quality and moisture resistance. The outer peripheral portion 43 is a boundary provided to secure a distance from the circuit area when the substrates 31 are stamped one by one.

As shown in Fig. 1(A) and (B), conductive circuits 33a are alternately formed on the Al substrate 31, and active components such as power transistors, small signal transistors or ICs are mounted on the conductive circuits 33a through solder 40, etc. 35. Passive components 36 such as chip resistors and chip capacitors are connected to external wires 39 through external connection terminals 38 to realize a predetermined circuit.

As shown in the figure, complex circuits are formed on the substrate 31 in a small space. The hybrid integrated circuit device of the present invention is characterized in that after forming an insulating resin 32 on the entire surface of an Al substrate 31, a complex circuit is formed on the resin 32, and then an external lead 39 is bonded to the substrate 31, and a transfer mold is used. The resin package 41 is directly integrally formed.

In the past, in the case of forming a hybrid integrated circuit device using a transfer mold, for example, the lead frame made of copper was processed by etching, punching or stamping to form wiring, isolation islands, etc., so it was impossible to form a conductive circuit like a hybrid integrated circuit. Circuits as complex as graphics. In the lead frame formed by the transfer die, when forming the wiring as shown in Fig. 1(A), it is necessary to fix it with suspension wires at different positions in order to prevent the lead wire from being bent. Thus, only a few active elements are mounted at most in a hybrid integrated circuit using a conventional lead frame, and the formation of a hybrid integrated circuit having a conductive pattern as shown in FIG. 2(A) is limited.

That is, by adopting the structure of the hybrid integrated circuit device of the present invention, the substrate 31 having complicated circuits can be formed using transfer molding. In the present invention, the substrate 31 is transfer-molded using a substrate with a high thermal conductivity, so the heat generated by the substrate 31 as a whole can be dissipated. Therefore, compared with the conventional hybrid integrated circuit device formed by transfer molding, since the metal substrate 31 is directly molded, the substrate functions as a large heat sink, and the heat dissipation is good, and the circuit characteristics can be improved. .

Next, a method of manufacturing the hybrid integrated circuit device of the present invention will be described with reference to FIGS. 3 to 8 . In addition, in FIGS. 4 to 8 , the drawings are omitted for processes that are clear without illustration.

Figure 3 is a process flow chart, including: the process of preparing the metal substrate; the insulating layer forming process; the copper foil pressing process; the partial nickel plating process, the copper foil etching process; the chip loading process; the wire bonding process; Die process; wire cutting process and other processes. As can be seen from the flow chart, the present invention realizes the process of forming the resin package by the transfer mold, although the resin package is formed by the injection mold at present.

As shown in FIG. 4(A), the first process of the present invention is the process of preparing a metal substrate, forming an insulating layer, press-fitting copper foil, and performing nickel plating.

In the step of preparing the metal substrate, the role of the substrate is prepared in consideration of heat dissipation, substrate strength, substrate moldability, and the like. At this time, especially when power transistors, large-scale LSIs, digital signal processing circuits, etc. are integrated into a small hybrid IC, heat dissipation is important because heat is concentrated. In this embodiment, an Al substrate 31 having a good heat dissipation and having a thickness of, for example, about 1.5 mm is used. In this embodiment, an Al substrate is used for the substrate 31, but it does not have to be particularly limited.

This embodiment can also be realized using, for example, a printed circuit board, a ceramic substrate, a metal substrate, or the like as the substrate 31 . As the metal substrate, a copper substrate, an iron-nickel substrate, or a compound composed of a metal with good electrical conductivity can be considered.

Next, the surface of the substrate 31 is anodized to form an oxide, and a resin 32 having good insulating properties, for example, epoxy resin is formed on the entire upper surface. However, if the withstand voltage is not considered, the metal oxide may also be omitted. Then, the copper conductive foil 33 constituting the hybrid integrated circuit is press-fitted on the insulating resin 32 . Nickel plating 34 is formed on the entire surface of the copper foil 33 in consideration of the adhesiveness to the thin metal wire 37 that electrically connects the copper foil 33 serving as an output electrode and the active element 35 , for example.

As shown in FIG. 4(B), the second step of the present invention is a step of forming partial nickel plating by etching and etching copper foil.

On the nickel plating 34, a selective mask is formed by leaving a resist only on the portion where the nickel plating 34 is required by known screen printing or the like. Then, nickel plating 34a is formed by etching, for example, at the portion where the extraction electrode is to be formed. Thereafter, the resist is removed, and a selective mask is formed by leaving the resist only on the required portion of the conductive pattern 33a constituted by the copper foil 33 again by known screen printing or the like. Then, the conductive pattern 33a of the copper foil 33 is formed on the insulating resin 32 by etching. Then, a resin overcoat layer is formed from epoxy resin on the conductive pattern 33a, for example, by screen printing. Of course, no resin overcoat layer is formed at the portion where the electrical connection is made.

As shown in FIG. 4(C), the third process of the present invention is a process of performing chip mounting and wire bonding.

Active elements 35 such as power transistors, small-signal transistors, or ICs, and passive elements 36 such as chip resistors and chip capacitors are mounted on the conductive pattern 33a formed in the previous process through conductive paste such as solder 40 to realize a predetermined circuit. Here, instead of using solder locally, it is also possible to use silver paste or the like for electrical connection. When mounting active components 35 such as power transistors and half-power transistors, a heat sink is provided between the active components 35 and the conductive circuit 33a in consideration of heat dissipation.

Next, when the active elements 35 such as semiconductor elements are mounted face-up, they are electrically connected by the thin metal wires 37 by bonding. The fine metal wire 37 electrically connecting the active element 35 and the conductive path 33a as described above is wire-bonded with the nickel plating 34a in consideration of the adhesiveness to the conductive path 33a constituted by the copper foil 33 .

Here, Al thin wires 37 are particularly used as the thin metal wires 37. Since it is difficult to perform spherical connection of the Al thin wires 37 in air, a stitch bonding method is used. However, in the stitch bonding method, the stitch portion is easily broken by the stress of the resin, and has a smaller modulus of elasticity than the Au thin wire, and is characterized by being easily crushed by the pressure of the resin. Therefore, care should be taken when using the thin Al wires 37 , especially when forming the resin package 41 . This point will be described later.

As shown in Fig. 5(A) and (B), the fourth step of the present invention is a step of conducting wire connection.

As shown in FIG. 5(A), external wires 39 for outputting and inputting signals from the hybrid integrated circuit are prepared. The outer lead wire 39 is made of conductive Cu, Fe—Ni, etc. material to serve as an input/output terminal, and the width and thickness of the outer lead wire 39 are determined according to the current capacity and the like. In the embodiment of the present invention, the strength and elasticity of the external wire 39 are required, which will be explained in detail in the next process, that is, the transfer molding process. Here, an Fe-Ne outer wire 39 having a thickness of, for example, about 0.4 to 0.5 mm is prepared. Then, the external lead 39 is connected to the external connection terminal 38 formed on the outer peripheral portion of the substrate 31 via the solder 40 . In this case, the connection means is not limited to solder, but spot welding or the like may be used for connection.

Here, as shown in FIG. 5(B), the present invention is characterized in that the external leads 39 are connected at a slight angle with respect to the mounting surface of the substrate 31 . In FIG. 5, the back surface of the substrate and the back surface of the external lead 39 are connected so that the angle formed therebetween is about 10 degrees. The melting point of the solder 40 connecting the external lead 39 and the external connection electrode 38 is set lower than the curing temperature of the thermosetting resin used in the next process, ie, the transfer molding process.

The fifth step of the present invention is a characteristic step of the present invention, and as shown in FIGS. 6 and 7, is a step of molding with a transfer mold. The hybrid integrated circuit substrate 31 is collectively packaged with a thermosetting resin 49 by transfer molding.

In order to collectively package the hybrid integrated circuit substrate 31 by transfer molding, the hybrid integrated circuit substrate 31 must be positioned within the mold cavity 70 as shown in FIG. 6(B). However, in the present invention, since the hybrid integrated circuit substrate including the back surface is collectively molded with resin, the hybrid integrated circuit substrate 31 cannot be brought into direct contact with the lower mold. Therefore, as described above, the lead frame 39 is angled. As shown in FIG. 6(B), a space is provided and fixed on the rear surface of the hybrid integrated circuit substrate 31 by press pins 47 . Similarly, a lead frame that can be used in common even if the number of pins is different is adopted.

Specifically, first, as shown in FIG. 6(A), the hybrid integrated circuit substrate 31 to which the lead frame 39 is soldered is transferred to the molds 44 and 45 .

Then, referring to FIG. 7 , positioning of the hybrid integrated circuit substrate 31 in the horizontal direction (here, the vertical direction and the horizontal direction of the paper) is performed by bringing specific portions of the lead frame 39 into contact with the guide pins 46 . Then referring to FIG. 6(B), the position in the thickness direction of the hybrid integrated circuit substrate 31 is fixed by pressing the outer peripheral portion 43 of the hybrid integrated circuit substrate 31 with the press pin 47 .

Specifically, the lead frame is held by connecting a plurality of lead wires 39 at two places of the first connecting portion 39d and the second connecting portion 39c as a frame. The number of wires leading out from the hybrid integrated circuit substrate 31 varies according to the scale of the electrical loops formed on the surface of the hybrid integrated circuit substrate 31 . However, in order to position the lead frame 39 in the horizontal direction, it is necessary to provide specific leads 39a and 39b which are in contact with the guide pins 46, and the space between them is fixed in the substrate size. Therefore, the number of wires varies depending on the scale of the electrical circuit formed on the substrate surface, and in this case, the number of wires other than the wires in contact with the guide pins is increased or decreased. In this way, a structure is adopted in which the lead frame is provided with missing teeth at an arbitrary position according to the scale of the electrical circuit formed on the surface of the substrate.

As shown in FIG. 5(B), the lead frame 39 is not parallel to the hybrid integrated circuit substrate 31, but is connected obliquely upward. The positioning of the hybrid integrated circuit substrate 31 in the thickness direction can be performed by utilizing the elasticity of the lead frame 39 as will be described later.

The guide pin 46 is a protrusion provided on the lower mold 44 as shown in FIG. 6(A), FIG. 6(B) and FIG. 7(A). Referring to Fig. 7 (A), the guide pin 46 is formed by the guide pins 46a and 46b which are in contact with the part where the specific wires 39a and 39b are connected to the first connecting portion 39d, and the guide pins 46c and 46d which are in contact with the first connecting portion from the outside. . That is, by bringing these four guide pins into contact with specific portions of the lead frame 39 , the orientation of the drawing surface of the lead frame 39 is fixed. Therefore, the hybrid integrated circuit substrate 31 is also fixed in the drawing direction.

Even when transferring hybrid integrated circuit substrates with different numbers of output and input terminals to be molded, since the specific wires 39a and 39b are spaced apart and the wires are removed, the mold and guide pin 46 can be shared.

As shown in FIG. 6(A) and (B), the upper mold 45 is provided with the press pin 47, and the lead frame 39 is bonded to the hybrid integrated circuit substrate 31 obliquely upward with solder as described above. Therefore, when the upper mold 45 and the lower mold 44 are fitted, the hybrid integrated circuit substrate 31 is pressed down by the pressing pin 47 so as to be parallel to the bottom surface of the lower mold 44 . In this way, the position of the hybrid integrated circuit substrate 31 in the mold cavity 70 is fixed in the thickness direction.

As shown in FIG. 7(B), the thermosetting resin injected from the gate 49 into the cavity 70 is injected so as to contact the side surface of the substrate 31 first. Then, the thermosetting resin injected as indicated by the arrow 49 is divided from the substrate 31 to the upper direction and the lower direction of the substrate 31 along the arrow 49 a. At this time, since the inflow width 56 to the upper portion of the substrate 31 and the inflow width 55 to the lower portion of the substrate 31 are substantially equal in width, the thermosetting resin can also flow smoothly into the lower portion of the substrate 31 . Also, especially since the resin fills the backside of the hybrid IC substrate 31 first, the hybrid IC substrate 31 does not tilt downward. In addition, the injection rate and injection pressure of the thermosetting resin are also reduced due to contact with the side surface of the substrate 31, and the influence of bending, disconnection, etc. of the thin Al wires 37 can be suppressed.

Thus, transfer molding can be performed after positioning the hybrid integrated circuit substrate 31 in the cavity 70 in this step, and there is no movement of the hybrid integrated circuit substrate 31 due to the injection pressure of the thermosetting resin. Therefore, the back surface of the hybrid integrated circuit substrate 31 can be encapsulated with a constant thickness of thermosetting resin having good thermal conductivity, so that a hybrid integrated circuit device with high voltage resistance and excellent heat dissipation can be manufactured.

In addition, since the melting point of solder 40 for connecting active components 35 such as power transistors, small-signal transistors, and ICs, passive components 36 such as chip resistors and chip capacitors, and external leads 39 is higher than that of thermosetting resins, even if it is not used, The potting resin 9 (refer to FIG. 9 ) of the conventional hybrid integrated circuit device is protected, and will not be remelted by heat during transfer molding, and will not shift the fixed position.

In addition, the second connecting portion 39c of the lead frame has the function of preventing the thermosetting resin from flowing out of the mold during transfer molding. Therefore, immediately after transfer molding is completed, as shown in FIG. 8 , the encapsulating resin continues to the second connection portion 39c.

As shown in FIG. 8, the sixth step of the present invention is a step of cutting the wire.

The resin that flowed out from the molds 44 and 45 at the thickness of the outer lead in the previous step, that is, the transfer molding step, is stopped by the second connecting portion 39c formed on the outer lead 39 and cured directly. That is, the lead space on the side of the resin package 41 from the second connecting portion 39c of the external lead 39 is filled with the outflowing resin 50, and the lead space from the second connecting portion of the external lead 39 is not filled with resin.

Then, punch the second connecting portion 39c and remove the outflowing resin 50 at the same time, adjust the length of the external lead 39 according to the purpose of use, for example, cut the external lead 39 at the position of the dotted line 51, so that each lead is independent, and can be used as an input and output terminal. effect.

Through the above steps, the hybrid integrated circuit device shown in FIG. 1 is completed.

As described above, the method of manufacturing a hybrid integrated circuit device according to the present invention is characterized in that the positioning of the hybrid integrated circuit device in the mold is performed by bringing specific leads into contact with guide pins provided on the mold in the transfer molding step. Thus, in the method of manufacturing a hybrid integrated circuit device according to the present invention, the mounting of the supporting member in the conventional method of manufacturing a hybrid integrated circuit device can be omitted, and the heat dissipation of the completed hybrid integrated circuit device can be greatly improved.

The hybrid integrated circuit device and its manufacturing method of the present invention have been described above for the fully molded hybrid integrated circuit device, but are not limited to the above embodiments. For example, a hybrid integrated circuit device may be formed in which the entire rear surface of the hybrid integrated circuit device is exposed. In this case, in addition to the above-mentioned effects, the effect of heat dissipation can also be obtained.

In addition, in this embodiment, the description is made on the case of a single-sided lead with external leads derived from one side of the substrate, and is not limited to this structure. In the case of two-sided leads and four-direction leads, the above-mentioned effect In addition, the transfer molding process can be realized in a state where the substrate is stabilized. In addition, various changes can be made without departing from the scope of the gist of the present invention.

In addition, when the lead wire 39a is not used as an electrical signal terminal, as shown in FIG. 7a, the lead wire from the second connection portion 39c to the substrate 31 side may be removed.

As described above, the manufacturing method of the hybrid integrated circuit device of the present invention can obtain the following excellent effects.

In the molding process, the hybrid integrated circuit substrate connected to the lead frame can be positioned in the mold cavity by making the part where the specific wire and the connection part are connected to the guide pin provided on the mold, and then wrap it with a thermosetting resin. Perform transfer molding. Thereby, the back surface of the hybrid integrated circuit substrate can be encapsulated with a thermosetting resin with good thermal conductivity at a constant thickness, and a hybrid integrated circuit device with good heat dissipation can be produced. Also, by making the intervals between the lead wires in contact with the guide pins constant regardless of the number of terminals in the hybrid IC substrate, it is possible to share a model even when transferring hybrid IC substrates with different numbers of terminals to be molded.

In addition, by providing a connecting portion where the lead frame is in contact with the upper and lower molds, it is possible to prevent thermosetting resin from flowing out of the mold from the gap between the leads during the molding process. By making the length of the connecting portion constant regardless of the number of terminals of the hybrid integrated circuit substrate, it is possible to share a model even when transferring hybrid integrated circuit substrates with different numbers of molded terminals.

Claims (9)

1. A method for manufacturing a hybrid integrated circuit device, characterized in that it includes the following steps: preparing a hybrid integrated circuit substrate electrically connected to circuit elements through a conductive pattern; using a conductive device extending externally as an input or output terminal Solder is fixed on the desired conductive pattern; the position of the hybrid integrated circuit substrate is fixed by clamping the conductive device with molded upper and lower molds for positioning; using a transfer mold using a thermosetting resin Batch molding the hybrid integrated circuit substrate. 2. The method of manufacturing a hybrid integrated circuit device according to claim 1, wherein the conductive means is a plurality of wires. 3. The method of manufacturing a hybrid integrated circuit device according to claim 2, wherein a plurality of said wires are connected at least at two connection portions, and said wires are held as an integral lead frame until the molding process is completed. 4. The method of manufacturing a hybrid integrated circuit device according to claim 3, wherein said lead frame has a first connecting portion at a terminal portion on the side where said lead wires lead out to the outside, and is aligned with the upper and lower sides during said molding. The part in contact with the model has a second connection part. 5. The method of manufacturing a hybrid integrated circuit device according to claim 3, wherein, in the molding step, the longitudinal side and the transverse side of the lead frame are arranged on the mold The guide pin contacts fix the position of the hybrid IC substrate. 6. The method of manufacturing a hybrid integrated circuit device according to claim 4, wherein said second connecting portion is removed after said molding step is completed. 7. The method of manufacturing a hybrid integrated circuit device according to claim 5, wherein the distance between the wires of the lead frame contacting the guide pins is the same as that of the wires derived from the hybrid integrated circuit substrate. The number has nothing to do, it is certain. 8. The method of manufacturing a hybrid integrated circuit device according to claim 4, wherein in the molding step, the continuous second connecting portion is brought into contact with the upper and lower molds to prevent the thermosetting resin from flowing out. external. 9. The method of manufacturing a hybrid integrated circuit device as claimed in claim 3, wherein said lead frame is led out from two opposite sides of said hybrid integrated circuit substrate.

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